“If people cannot write well, they cannot think well, and if they cannot think well, others will do their thinking for them.” - George Orwell Orwell summed things up beautifully!
Here is a wonderful description of rhetoric, which is at the core of my AP Language course. It's from a Blog post by Sam Leith in the New York Times titled "Other Men’s Flowers":
Rhetoric, simply put, is the study of how language works to persuade. So any writer seeking to make a case, or hold a reader’s attention — which is more or less any writer not in the service of the Democratic People’s Republic of Korea — has something to learn from it.
If the classical orators have modern counterparts in the realm of the written word, pre-eminent among those counterparts are the authors of opinion pieces. Here is persuasion overt, persuasion front and center. The techniques that served Cicero will just as effectively serve modern writers of opinion.
Open a book of rhetorical terms, and you will meet a lot of gnarly looking Greek and Latin words. Apodioxis and epizeuxis sound like diseases you wouldn’t especially want to catch. But, pilgrim, be not afraid. The figures — all the different twists of language that rhetoric describes — are sometimes called the flowers of rhetoric. Think of these words as the botanical names for those flowers, and remember what Shakespeare said about roses and their names.
Using classical techniques is not, in itself, a different approach to writing: it’s simply a way of thinking more consciously about what you’re doing. Terms such as antithesis, which is the technique of setting two terms in opposition, are ways of labeling what any prose stylist does by habit and instinct. Like the bourgeois gentleman of the playwright Molière — amazed to discover in middle age that he’d been speaking prose all his life — you’ve been using the figures since long before you could name them.